190 tire on rear

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krotchrocketgrampa

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this has probably been beat to death already, but here gose.

what difference will a 190 tire do as apposed to a 180 and is anyone doing this ???????????

 
this has probably been beat to death already, but here gose.
what difference will a 190 tire do as apposed to a 180 and is anyone doing this ???????????
It has been beaten to death. Given the same width wheel rim (5.5" on FJR), the wider 190 changes the tire's profile, at least of the shoulder of the tread area (steeper) compared to that of the 180 that the engineers specified with that wheel. Kevin Cameron does a good job of explaining why it's not optimum to run a wider tire than the wheel rim is designed to take in his "Sportbike Performance Handbook", but several here will insist that it is otherwise and recommend running 190s.

On other bikes where it is a lot easier to put different wheels on the bike than the FJR with its shaft drive hub, the same discussion takes place, and most who go to a 190 from a 180 put on a 6.00" or 6.25" rear wheel to accommodate it. This was pretty common on Blackbirds, for example. In that case (with no issue of changed profile), the wider 190 supposedly slows turn in a little compared to the 180, all other things being equal. The primary performance advantage of the wider tire is usually a larger contact patch to handle greater horsepower.

 
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Are you looking to gain something? If you don't have a particular goal for the change, you might as well stick with the stock size.

It's been done. It works. Not sure it's really any better or worse than the 180 on the street.

 
The aspect ratio is quite a bit different between a 190/50 vs a 180/55 and I can't see any advantage at all in mounting a 190 on your FJR. And, you will be out a few more bucks on the 190. I think the engineers knew what they were doing putting a 180 on. Had a Blackbird in years past and the 180 worked just fine in the canyons and on the track. It allowed me to grind down pegs, converter, rear pipes and fairing up to the 2nd opening and hold a line.

 
To amplify on the Blackbird experience (though I've never had a 190 on either of mine).

I have a friend (very good rider) with a '98 Blackbird (who just bought an '09 Connie as a second bike and may be coming along to WFO9 and WCRR) who went in for a tire and the shop had no 180s, so they put on a 190 as part of a set of Pilot Powers. I had a '97 Blackbird running Pilot Powers also, but with the stock 180 on rear.

On a ride in some hard twisties in the fall of '05, he was having trouble keeping up due to some weirdness in the transitions -- said it felt like the rear was about to step out when leaned way over. We stopped for a break at Loon Lake, started talking about it, and had the chance to compare identical types of tires on nearly identical bikes with similar wear lives left -- one a 190, one a 180. His rear tire was noticeably more squared off from wear than mine, and he reported that it wasn't as much of a bitch leaned all the way over when the tire was new as it was now with maybe 33% of tire life left. Seriously -- the wear on our rear tires was very different. He went back to 180s on the rear and reported that the problem was cured.

Cannot say that the same thing would happen on an FJR, or with PR2s vis Powers, or with different riders, etc.

 
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When you think about it a 190 on a rim that is really too narrow will result in the tire taking on a shape that is more bulbous and at anearly any point in the lean the tire will have an indication of more lean angle. Could account for it breaking loose. I'd say unless you're willing to get a wheel that fits a larger tire and the bike, stick with the 180. And, do ya really need it.

 
A 5.5 rim is not to narrow for a 190. Check the recommended rim sizes.. Some Ducs come thru with a 190 on a 5.5 rim. A 190/50 is about 18mm smaller in circumference than a 180/55 and a few mm smaller in diameter. Only Rossi could tell the difference in handling. No advantage to the 190 except IMHO it looks a little better and that is why I use it. Costs a few bucks more. It is exactly 10 mm wider than a 180 on the FJR rim. It is also 2 mm narrower that the oem BT 020 180 that came on my '06. No, your balls won't fall off if you use a 190 but they will if you mount a CT!.

 
I was looking at a set of PRII's tires at a shop and placed the 190 rear up against the 180 and noticed the 190, although a little wider, is not as tall. So all you are really going to accomplish is throwing your speedometer off even more than it already is coming from the factory. With a smaller diameter tire, you'll rack up more miles than you actually ride (not a good thing), not to mention the speedo is usually already off by 3-5mph showing faster than you're actually going, which is also adding mileage.

I'd just stick to OEM sizes, you are probably better off all the way around.

 
this has probably been beat to death already, but here gose.
what difference will a 190 tire do as apposed to a 180 and is anyone doing this ???????????
I had an '86 FJ1200 as my last bike with the "right" fork springs, shock, engine mods and such. Worked GREAT! Untill I listened to a fellow that said it would be "cool" to mount a wider tire since it would "fit".

Wider tire, narrow rim, equaled a bouncy ride, unstable corner ride, due to the rim was not directly supported by the sidewalls anymore, but kind of sinking into the tire when it was stressed by cornering and/or road irregularities. Go with what the bike mfg recomends and designed the bike to use!

 
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